1 - Hercules - Just herc it ๐
2 - Hulk - Best even against skill champions, 80% of the Battlerealm are possible to stun
3 - Odin - Father of all can inflict 60% damage with SP2
4 - Shang Chi - Awesome against many defenders, one hit guy.

5 - Red Skull - Yes, Red Skull. Because Red Skull is amazing as Attacker too. If you manage to bring Red Skull to Sp2 , Red Skull will degen the rival the entire health, or if not, almost 80%. So put Sigs on Red Skull till 200, ascend him , progress Red Skull to the max possible and you will have all benefits from Red Skull. Also, Red Skull is great on Incursions.
All tips from the Legendary Paragon ๐๐ก๏ธ๐๐ฟ
Now, its your time
Enjoy and have fun ๐ฅณ